BoilerFaultCodes 166 High
Boiler Fault Code 166
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 166 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has stopped working because it cannot confirm that the fan is clear of old gases before starting the ignition process. (As reported on ECA FELiS FL 50 HM)
Pick your boiler brand for the 166 fix
Source
Information for the 166 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026